Manufacture of alkaline curing salt composition



United States Patent 7" 3,193,396 MANUFACTURE (PF ALKALWE CG SALT CGMPGSITEON Louis Sair, Evergreen Park, EL, assignor to The Grihith Laboratories, Inc, Chicago, lllh, a corporation of Illinois No Drawing. Filed Feb. 12, 1964, Ser. No. 342,838 10 Claims. ((31. 99-222) The present invention relates to a non-caking meat curing salt composition for providing a nitrogen-containing salt selected from the group consisting of alkali-metal nitrite and alkali-metal nitrate, and containing alkaline material for elevating the pH of the meat to be acted upon by said nitrogen-containing salt. In particular, it relates to such a composition containing sodium hydroxide as the alkaline content, especially in the presence of alkali-metal nitrite.

Fresh meat has a normal pH in the range from 5.5 to 6.2, due largely to a content of lactic acid formed at slaughter due to break-down of the blood and muscle sugar, namely, glycogen. The present invention is not only directed to providing a curing salt composition capable of fixing the cured color of the meat, but also capable of adjusting the pH upward to improve the Water binding capacity of whole meat, and the emulsifying properties of comminuted meat.

Curing salt compositions conventionally are mixtures having a major portion of sodium chloride, which permits the meat packer more accurately to measure the ingredients of minor proportion.

Curing salt compositions are commonly shipped in drums from a supplier to a meat packer, who removes portions from the drums for immediate use. When such compositions were made by mechanically mixing crystals of the separate salt ingredients, complaints by Government control authorities arose as a result of using such a mixture. The content of the nitrite salt used in curing is limited by such authorities. It was ascertained that in shipping and in distributing such bulk quantities of the mechanical mixture, gravitational separation frequently took place with the result that there were formed portions relatively deficient and portions relatively richer in nitrite salt. Use of the richer portions frequently resulted in excess use of nitrite in the curing process.

It is known that when such a mixture is very finely ground, the danger of separation is minimized, but other difiiculty is encountered. Very fine particles tend to cake merely due to their size. This tendency makes the particles less mobile, thus minimizing separation. The longer such a fine-ground mass stands, the harder it cakes, making it more diflicult to remove a portion of the cake for use.

In addition to using curing salt compositions, some packers employ one or more of edible phosphate salts for improving water-binding properties. These are commonly supplied separately from the curing salt composition. In attempts to supply phosphate salts as a component of the curing salt composition, difiiculties are encountered, such as mechanical separation or settling, dustiness, and tendency to cake in finely ground mixtures. Because the U.S. Government sets limits on the amount of nitrite and phosphates which can be used, under its jurisdiction, it is not permitted to use mechanical mixtures containing individual phosphate salt crystals.

U.S. Federal regulations permit the use of pyrophosphates, polyphosphates and orthophosphates, other than the normal alkali-metal orthophosphates, because of their mild alkalinity. Stronger alkalis such as trisodium phos- 3,l93,3% Patented July. 6, 1965 phate, sodium carbonate, sodium hydroxide and their potassium equivalents function as desired, but are not permitted. Such strong alkalis are too corrosive and dangerous to handle and tend to dustiness.

In improving the water-binding properties of meat, the elevated pH resulting from use of alkalis is the important factor. radical remains as a residue in the meat. If alkali-metal carbonates and hydroxides were permitted, no such undesired residue would be formed. Also, cost-wise, the alkaline agent would be less expensive by providing alkalinity with carbonate or hydroxide.

Among the alkaline agents available for the present invention are the alkali-metal carbonates and hydroxides. These are preferred because they introduce no acid residue as do, for example, certain salts derived from phosphoric acid. The hydroxides are more desirable for all purposes, since there is no possible generation of gas bubbles in a liquor or within a meat mass, as can result from the use of carbonates.

Sodium or potassium hydroxide as a single entity inof irritation to the skin in contact with it and with a greatly reduced hygroscopicity.

It is a general object of the invention to prepare a gran-. ular curing salt composition with a particle-size distribu tion such that all the size fractions thereof are substantially uniform in chemical composition with respect to at least one of the chemical ingredients.

It is a particular object to produce such a composition which is free-flowing, non-caking, and also non-hygroscopic when alkali-metal hydroxide is present.

The process generally is to prepare a finely divided mixture of the ingredients which is uniform in composition, mechanically to apply pressure in a manner to produce bonded caked forms of the mixture, and then to fracture the cakes to provide a composition such that the size-fractions are aggregates of all the original particles and fractions thereof have substantially the same composition as the original mixture with respect to at least one of the ingredients.

To achieve the desired results a uniform mixture of suitably finely-divided crystals is purposely bonded to caked or agglomerated form by mechanical compaction. To produce individual particles of substantially the same composition the caked or agglomerated forms are ground or comminuted to a desired fineness, but of a minimum coarseness predetermined as indicated hereinafter. Comminution is best done and controlled by passing the cake through the nip of grinding rolls set apart to control the size. Several passes are preferred, as by passing the ma terial through a bank of such set rolls, for example,

three in number, each following set being more closely spaced.

Caking may be effected in one way by mechanically squeezing together the particles of the original mixture.

In doing this with phosphates, the phosphate One way is to extr'ude a rod-like form and to chop oif pellets as extruded. Pellets must not be smaller than a minimum size predetermined as indicatedbelow. Another way is to pass a mass of the original crystals through the nip of heavy compression rolls, exerting heavy pressure, so that sheet-like forms are produced of thickness, for example, A to Aa inch. Such forms may be, further fragmented to facilitate further comminution asdescribed. I 1

The final product need not have particles of uniform size and its particle-size distribution must yield size-fractions all having substantially the same composition as the original mixture with respect to at least one critical ingredient, and preferably to all. These are-criteria for limiting the fineness of the ultimate product. These criteria are not necessarily those of the original mixture, \because the very act of compacting the original mixture can fracture larger sizes to fill spaces in producing the caked for-ms. Therefore, the ultimate smallest particlesize distribution of formed pellets, or of size-reduced caked-forms is determined by analytical procedure for a given original mixture and the processing thereof. The size fractions of the ultimate product must have an acceptable uniform composition with respect to one or more components which are critically controlled in use of the product, especially the nitrite content.

The larger the sizes of the ultimate product up to the original caked forms, the more certain is the composition to be uniform. The finer the ultimateproduct is to be, the more important it is to check the composition lby ana'lytical control. I v

7 Although large cake sizesmay be shipped or stored as the ultimate product, that is not commercially practi-.-

as trisodium phosphate, disodium phosphate, sodium tri- V polyphosphate, tetr-asodium pyrophosphate, sodium carbonate, sodium bicarbonate, and the potassium salts corresponding to said sodium salts.

Where phosphates are used, it is observed that the An average size is preferred which U.S. regulations permit as much as 27 lbs. of phosphate per gallons of pickle when pumped to 10% of added weight in curing meat such as hams. Where sodium nitrite is used in making a pickling brine, not over two p unds of sodium nitrite may be used per 100 gallons, when pumped to 10% increase in Weight. p

Typical compositions for a curing salt are given in Table I for the purpose only of illustration. be used in amount of 35' pounds per 100 gallons of pickle.

Throughout this specification, the term alk-alinity of acompositionv is employed. It is the measure of ml. of 0.1 N"hydrochlo'ric acid required to titrate to pH of 6 a solution of one gram of the composition in 100 ml. of water.

These may.

In producing Compositions A through E, 250 pounds of the raw material ingredients were blended. These were sampled for analysis for particle-size distribution, for the alkalinity of the size fractions, and for their nitrite content. a

The remainder of each batch was ground fine so that substantially all of it passed a ZOO-mesh screen. The fine-ground compositions were then compacted, bot-h dry, and with 2% of added water. After compaction at various pressures, the compacted material was dried, then ground.

COMPOSITION A.DISODIUM PHOSPHATE DUOHYDRATE The raw materials used had a particle-size distribution as follows:

Table II Percent by weight Mesh Through 200- 6 3 {59 7 The mechanical mixture of the raw ingredients was analyzed for particle-size distribution, and the fractions were analyzed for nitrite content and for alkalinity, as

set forth in Table III.

' Table III demonstrates that the original mixture easily separates into fractions not uniform in nitrite content and in alkalinity.

'After grinding the original mixture. so that nearly all of it passes a ZOO-mesh screen, the particle-size distribution was determined, and the size-fractions analyzed for nitrite content and alkalinity. The results are shown in Table IV.

Table 'W Mesh on 150 On 200' On 270 Through The mixture (percent) 11 32 22 35 Sodium nitrite (percent) 3. 25 3. 4. 65 r 4. 55 Alkalinity V 56 54. 2 53. 5

The uniformity of composition is improved, but the fineness leads to dustiness, difficulty of dispersion in making a pickle, and possible caking.

The fine-ground mixture was then compacted between rolls using various pressures, measured as pounds per ilinea'r inch of roll, 'bothdry and with 2% added water.

The compacted bodies were then ground and the same analyses made, as shown in Table V.

Table V Example Pressure, On 50 On 100 On 200 Through lbs/in. 200

A-l Dry 3, 600 Too soft-Crushes with fingers. A-2 Dry 7, 200 Too soit-Cannot be ground.

Mixture (percent) 41 16 31 12 A-3 Dry 10, 800 Nitri (pereent) 4. 3 4.8 4. 5 3. 95

Alkalinity 53. 2 53. 53. 2 52. .A-4 2% H O 7, 200 Too softCannot be groun Mixture (percent) 39 27 18 16 A-5 2% H O 10, 800 Nitrite (percent) 4. 55 4. 8 5. 3 5. 55

Alkalinity 54. 1 53. 5 53. 5 53. 2

The uniformity of alkalinity is excellent. The uniformity of sodium nitrite content falls within 10% deviation from the median value between the two extremes, such deviation being permitted in this circumstance in Federal The preceding initial Composition B was ground fine and analyzed as follows:

regulations. Table B-IV The same procedure has been followed with composi-tions B, C, D and E, and the same series of tables are given for each composition. To facilitate comparison, M9811 the corresponding tables are identified by the same Roman number preceded by a letter designating the com- On 150 On 200 On 270 gg position.

COMPOSITION B.SODIUM TRl'POLY- rll l mixturepercenwbnfl 11 3g 9 22 65 32 5 0 ium nitri e percen 3.25 .5 PHOSPHATE Alkalinity 50.0 54.2 54 53.5

Table B-II Percent by weight of fractions of initial raw materials Mesh The uniformity is satisfactory, but the composition is Na P Oru NaNO; NaNO 35 so fine it is dusty, difiicult to disperse in a pickle, and likely to cake on storage. By compaction and grinding to 0 37 14 a coarser particle-size distribution, the product can be on 200 $2 i made free-flowing, non-caking, non-dusting, easy to dis Through 200 90.0 3 s9 perse in a pickle and uniform in composition as shown in 40 the following table.

Table B-V Mesh E 1 r am e 1'1. x p sh 01150 On 100 On 200 Through J Mixture (percent) 36 14 7. 5 42 18-1 Dry 7,200 Nitrite (percent) 4.55 4.40 5.10 4.30

-. 38 19 19 24 13-2 Dry 10,900 4.10 4.10 4.8 4.00

l l 45 2 2 2 2 2 2 10 13-42 HO 9,000 4.

% 2 {Alkalinity 39.7 89.8 39.8 39.4

1 Not determined.

All of the foregoing are satisfactory in unformity and are non-caking, free-flowing, free of dustiness, and disperse readily in making a pickle.

COMPOSITION C.TETRASODIUM SPHATE Table B411 PYROPHO Table 0-11 ANALYSIS OF INITIAL MIXTURE Percent by weight of iractions Mesh of initial raw materials Mesh On 50 011100 011200 Th2r0ugh 7O Nar12O7 NaNOz NaNO;

i it it The mixture (percent) 2 5 21.0 72.0

' 61.5 31.25 3.75 0.3 19 14.7 11.8 iiiilifitl fltff ltllflu 4.0 21.8 44.8 39.8 Through 200 s0 3 59 The variations evident in the above table are due to the original coarseness of the sodium hydroxide. By fine grinding the above initial mixture, the product analyzes as follows:

Table VII Figures in percent Mesh A B C D E NazHPO N55P30 0 N84Pz0 N21200:; NaOH On 50 68 O 0 1.2 On 100 24 2.5 1 7.2 On 200. 2 7. 5 19 50. 5 Through 2O 6 9O 80 41. 1

The following Compositions AA through BB were made in the same proportions of ingredients as the Compositions A through E, respectively, as given in Table I above.

Table E-I V COMPOSITION AA.DISODIUM PHOSPHATE DUOHYDRATE Mosh The mechanical mixture of its ingredients which are characterized in Tables VI and VII Was analyzed as On 150 On 200 On 270 Through follows;

270 Table AA-VIII The mixture (percent) 12. 5 12. 5 22. 5 52. 5 Sodium nitrite (percent)--. 4. 3 4. 05 5.15 3. 75 Mesh Alkalinity 9a. 3 95. 5 86.7 90. 2

On 50 On 100 On 200 Through The nitrite variation is substantial. The product tends 200 r nd omnlrill difbe dusty corosmei f i c e c a y The mixture (pcrcent) 04.0 25.0 7.0 4.0 ficult to handle. On storage 1t C es sodlum nltrite (percent)-.. 0.3 7.15 25.6 32.4 By compaction and grinding to a coarser mesh, these Alkflllmty 410 drawbacks are overcome, as shown in the following table:

Table E-V Mesh Pressure, Example lbs/in.

On 50 On 100 On 200 Through Mixture (percent) 46. 0 16.0 12. 0 25.0 E-l Dry 9, 000 Nitrite (percent) 4.4 4.56 5.3 3.80

Alkalinity 9s. 1 97. 3 91. 0 s7. 6 Mixture (percent) 57.0 15. 0 10. 0 18.0 15-2 2% Hi0 9, 000 Nitrite (percent) 4. 45 4. 5s 4. 85 3.85

Alkalinity 99. 4 98. s 91. 6 88. 4

The compaction appears to lock the sodium hydroxide into the agglomerates in such a way that the hygroscopicity is not exerted to the degree it is in the original mechanical mix. The product is free-flowing, and not ad versely hygroscopic. The dilficulties arising from a content of sodium hydroxide are greatly lessened because of locking the sodium hydroxide into an agglomerate.

All of the foregoing examples were made by fine-grinding an original mixture, compacting and then grinding to a coarser mesh than the fine-ground mixture. It is not always necessary to fine-grind the original mixture, as illustrated below.

A new series of compositions was made from mechan ical mixes of dilferent lots of raw material ingredients, but without comminuting the mechanical mixtures before compaction.

The following table gives the particle-size distribution of three new lots.

Table VI NaNOg NaNO NaCl Through 200 The following table gives the particle-size distribution of the alkaline agents, these being the same as given hereinabove.

Said Composition AA was compacted at 9,000 lbs/in. with 2% of added water. After drying the resulting agglomerates, the compacted material was ground to the The nitrite uniformity is not over 10% deviation from the mean nitrite content of 5.00. The fraction highest in nitrite is the smallest one passing through ZOO-mesh, which in commercial practice would be recycled. The alkalinity is quite uniform. This table shows great improvement over the mechanical mix characterized in Table AAVIII.

COMPOSITION BB.SODIUM TRIPOLY- PHOSPHATE The mechanical mixture of its ingredients which are characterized in Tables VI and VII was analyzed as The results in the preceding table compared to those in follows: a Table C-V again establish that before compaction the ,particle-size must not be too large, and the finer the better. Table BB-VIIl COMPOSITION DD.SODIUM CARBONATE I'M-55h V The mechanical mixture of its ingredients which are characterized in Tables VI and VII was analyzed as fol- On 50 On 100 On 200 Through l ,The mixture (percent) 1,0 3.0 11.0 851) m VDDTVIH Sodium nitrite (per'ee' 22.0 52.0 32.0 0.85 Alkalinity"; 2.8 60.0 26.6 32.8 Mesh On 50 On 100 On 200 Through The non-uniformity of the mechanical mix is evident,

but can be remedied by compaction and grinding to .a g g 32.8 2%.? 2%.

coarser mesh than given in the abov'e table. The me- Alkalinity 1 112:0 128:0

chanical mix BB with 2% added water was compacted with 10,800 lbs./in. pressure, then. dried and ground to the following mesh: 7 a a 1 Table BB IX The mixture with 2% added water was compacted with 10,800 lbs/in. pressure. Then, the agglomerates were dried and ground to the following mesh? Mesh On 50 On 100. On 200 Th r rr h v "Ta l DDL X The mixture (pereent). 45.0 10.0 10.0 22.0 1 Mesh Sodiulnnitrite (percent).-. 4.1 5.4 5.10 3.15 Alkalinity 30.0 29.2 29.4 30.4 o 50 Onldo 015200 Tmofigh V 5 'gIhe: mixtgi re pzere'enty in; 3212 22.8 12.0 23.0

oimnn Y11 The result compared to that of compositionp n Table xnre iirrit ufn iif 80.3 68.7 05.1 80.0 B-V shows that the particle-size distribution before compaction should not be too large, and the'finer the better. Q a Pram!cal lfmlt y be determmed by The-nitrite uniformity'is'only'slightly over 10% deviaexpel'lence with each formulatwn- 0 tion fromthe mean between the extremes, showing great improvement by compaction and grinding to a coarser COMPOSITION CC-' TETRASODIUM mesh The variations in alkalinit are also reatl im- PYROPHOSPHATE pr-ove'd' y g y The mechanical mixture of its ingredients which are COMPOSITIQN HYDROXIDE characterized in Tables VI and VII was analyzed as follows: The mechanical mixture of its ingredients which are characterizedin Tables VI and VII was analyzed as follows- VIII T CC Table EE-VIII s Mesh 100 0 200 Th 0 h On 50 On 11 {Doug On 50 On 100 On 200 Through The'mixmret ereent 1.0 7.0 25.0 00.0 Sodium Nitrite (peree nt) .1 11.3 .40. 0 8.2 0. 85 The 1 tu e (p r t). 85. 0 '49. 0 1. 0 Alkalinity 2. 8 26. 9 52. 7 02. 1 d1um N1tr1te (percent) a 0. 4 3. 6 15. 6 16. 0 Alkalimty 224. 0 20. 0 4. 4 3. 0

The mechanical mixture after adding 2% of water was compacted at 7,200 lbs./ in. pressure; Then,the agglomerates were dried and ground to a mesh as follows:

After compaction at 10,800 lbs/in. the agglomerates were ground to the following mesh:

Table CC-IX Table EE IX v Mesh j Mesh onso "011500 011200 Y 'Th r ou' h On 50 on 100 On 200 Tir r eugir The mira'rre percent) 4'2. 0 18.0 12. 0 29. 0 The mixture (percent). 50. 0 19. 0 8.0 18.0 Sodium nitrite (percent) 4.4 5. 85 5.4 2.85 Sodium nitrite (percent) 3 4'. 5 '4. 0 4.23 Alkalinity 50.0 40.2 40.4 40.9 Alkalinit 104.0 07.4 57.5. 00.0

The nitrite value is within of the mean value. The alkalinity has been distributed. Compared to the original mixture, the product is less corrosive, less dusty, less hygroscopic, and easier to handle. It dissolves more slowly than the sodium hydroxide ingredient and can be added to water Without excessively rapid generation of heat. This shows that it is more desirable to use a finer grind for the original mixture.

The following description shows the eifect of using compositions of this invention in curing hams. Table X shows five compositions as designated M, N, O, P and Q, made according to the compacting procedure herein described.

Table X Composition M N O P Q Sodium nitrite (percent) 4. 6 4.6 4.6 4. 6 4.6 Sodium nitrate (percent)-- 3.4 3.4 3.4 3.4 3.4 Sodium hydroxide 35 25 20 10 Sodium chloride. 57 62 67 72 82 Alkalinity s1 69 5s a 23 pounds of the Compositions M through P were made up to 100 gallons of pickle, which was used to pump hams to 10% added weight.

In pumping hams to 10% added weight having initially a pH of 6.1, it is desired to raise the pH by 0.2 to 0.3 unit of pH. The compositions made into pickles as described above have been so used and effect final pH in the hams as set forth in Table XI.

Table XI Composition: pH of cured hams M 6.7

From the foregoing, it appears that the content of so dium hydroxide in Composition Q is near the minimum required for pickles containing 35 pounds per 100 gallons, when pumping hams to 10% added weight.

The nitrite and nitrate salts may be combined into a physically homogeneous fusion product, and that product used to supply the two salts.

The following Table Xi! gives the fusion points of such salts, and of certain mixtures thereof.

Table XII Approximate Substance melting point, C. Potassium nitrate 337 Potassium nitrite 297.5

Sodium nitrate p 308 Sodium nitrite 271 Sodium chloride 804 Mixed sodium nitrite, 60%sodium nitrate,

There are some peculiar facts about the fusion points of mixtures. When dry nitrites and nitrates are mixed for fusion, the melting point is sharp when the same metal base, such as sodium, is used in both salts. When the metal bases difier, the melting point is spread over a wide range. This is believed due to a shifting of the equilibrium between the two salts forming perhaps four salts. It is also noted that Where the metal bases differ the melting point is lower than when the metal base is the same for both salts.

Although the examples given above disclose the grinding of a mixture of the constituent particles, it is to be understood that supplies of the separate constituents may be ground, and then mixed.

In carrying out the invention, the caked forms are reduced in size varying in smallness from a coarseness which packs tightly for shipment, which does not cake because of fineness and which has a substantially uniform content in its size-fractions with respect to at least one critical ingredient. For example, the caked forms may be ground to coarse sizes, even such as rock salt, to serve the mechanical purposes of the user. It is noted, however, that the invention has been explained and exemplilied by reference to an ultimate fineness much greater than need be practiced. The preferred size for general use is one of which substantially all the particles pass a 16-mesh screen and remain on a mil-mesh screen.

The invention is not limited in saleable products to those which contain the entire product of grinding a cornpacted mass. Since the final product has fractions of graded sizes, any grind may be fractionated to select from its fractions a composition of one or more fractions within a predetermined range of particle sizes. Such fractions as are rejected in doing this may be used as raw material for recycling through the compaction procedure, whether they be at the coarser end or at the finer end. In consequence, the original mass may be, or may include, particles which are aggregates of the component salts.

A granular form of curing salt of moderate fineness in the form desired by the meat packers, not only for mixing it directly in products for ground meat and for rubbing onto heat, but also for ready weighing and dissolution in forming brine.

The salt compositions which are the subjects of the present invention may contain additives, such as cane sugar, corn sugar, ene-diol compounds, such as sodium isoascorbate, and seasonings, which are compatible with the alkaline content and which function in the treatment of meat. It is to be understood that increase in the kinds of particles which constitute the original uniform mixture has a controlling effect on smallest permitted sizes of the ultimate product to maintain the desired uniformity of composition. I

Although small amounts of alkaline material have been used in dry solid curing salt compositions as a buiferlng agent to protect one or more ingredients of the composition, the buffering amount is small and far below the 40 to 92 parts of alkali used per 8 parts of the selected curing salt, as given in Table I above.

The invention is not limited to or by the details and examples given above to illustrate and explain the invention, and numerous changes and modifications are contemplated as fallin within the scope of the invention as expressed in the appended claims.

This application is a continuation-in-part of my earlier application Serial No. 223,269, filed September 12, 1962, now abandoned.

I claim:

1. The method of producing an alkaline curing salt composition, which composition comprises bonded aggregates of physically homogeneous particles of curing salt selected from the group consisting of alkali-metal nitrite, alkali-metal nitrate and mixtures thereof, and chemically homogeneous particles of edible-ion alkaline material in kind and quantity to elevate the pH of meat for which saidcomposition is used, which method comprises bonding to caked forms a granular mixture of finely divided particles of the constituents of said composition which mixture is substantially uniform throughout 'in composition, by compacting said granular mixture with an effective mechanical pressure sufiicient to lock the particles to each other so that when the said caked forms are reduced in size the size-fractions have a substantially uniform composition, and then reducing the'size of said caked forms which are substantially dry to provide a mass of such particle-size distribution that all the size-fractions thereof have a'substantially uniform composition.

2. The method of claim 1 wherein the caked forms are ground to a free-flowing non-caking fineness.

3. The method of claim 1 wherein said granular mixture contains sodium chloride crystals. V

4. The method of producing an alkaline curing salt composition, which composition comprises bonded aggregates of physically homogeneous particles of curing salt selected from the group consisting of alkali-metal nitrite, alkali-metal nitrate and mixtures thereof, and chemically homogeneous particles of edible-ion alkaline material in kind and quantity to elevate the pH of meat for which said composition is used, which method comprises mechanically mixing supplies of the constituent particles, grinding the resulting mixture to agranular mass which is substantially uniform throughout in composition, bonding to caked forms said resulting granular mass by compacting said granular mass with an eifective mechanical pressure sufficient to lock the particles to each other so that when the said caked forms are reduced in size the size-fractions have a substantially uniform composition, .and then reducing the size of said caked forms which are substantially dry to provide a mass of such particle-size-distribution that all the size-fractions thereof have a substantially uniform composition.

5. The method of producing an alkaline curing salt composition, which composition comprises bonded aggregates of physically homogeneous particles of curing salt selected from the group consisting of alkali-metal nitrite, alkali-metal nitrate and mixtures thereof, and chemically homogeneous particles of alkaline material selected from the group consisting of alkaline alkali-metal orthophosphates, alkali-metal tripolyphosphate, tetrasodium and tetrap otassium pyrophosphate, alkali-metal carbonates and alkali-metal hydroxides, which method comprises mechanically mixing supplies of the constituent particles, grinding the resulting mixture to a granular mass which is substantially uniform-throughout in composition, bonding to caked forms said resulting granular mass. by compacting said granular mass with an eifective mechanical pressure sufficient'to lock the particles to each other so that when the said caked forms are reduced in size the size-fractions have a substantially uniform composition, and then reducing the size of the resulting caked forms which are substantially dry to a free-flowing orthophosph-ates, alkali-metal tripolyphosphate, tetrasodium and 'tetrapotassium pyrophosphate, alkali-metal carbonates and alkali-metal hydroxides, which method comprisesbonding to caked forms a granularmixture of particles of the constituents of said composition which mixture is substantially uniform throughout in composition, by compacting said original mass with an effective mechanical pressure suficient to lock the particles to each other so that when the said caked forms are reduced in size the size-fractions have a substantially uniform composition, and then reducing tliesize of said caked forms which are substantially dry to provide'a mass of such particle-size distribution that all the size-fractions thereof have a substantially uniform composition.

8. The method of producing an alkaline curing salt composition, which composition comprises bonded aggregates of physically homogeneous particles of curing salt selected from the group consisting of alkali-metal nitrite, alkali-metal nitrate and mixtures thereof, and

chemically homogeneous particles of alkaline-material selected from the group consisting of alkaline alkali-metal orthophosphates, alkali-metal tripolyphosph-ates, tetrasodium and tetrapotassium pyrophosphate, alkali-metal comprises bonding tocaked forms a granular mixture of particles of the constituents of said composition which mixture is substantially uniform throughout in composition, by compacting said granular mixture with an eifective mechanical pressure sufiicient to lock" the particles to each other so that when the said caked forms are reduced in size the size-fractions having a substantially uniform composition, and then'reducing the size of the resulting caked forms which are substantially dry to a particle sizedistribution coarser than that of said'mixture and characterized by size-fractions of substantially uniform composition. H I

9. The method of producing an alkaline, curing salt composition, which composition comprises bonded aggregates of physically homogeneous particles of curing salt selected from the'group consisting of alkali-metal nitrite, alkali-metal nitrate'and mixtures thereof, and chemically homogeneous'particles of edible-ion alkaline material in kind and quantity to elevate the ,pHof meat for which said composition is used, which method comprises bonding to caked formsa granular mixture of finely ground particles of constituents of said composition which mixture is substantially uniform throughout in composition and which contains a small amount of added water, by compactingsaid granular mixture with an effective mechanical pressure sufiicient to lock the particles to each other so that when the said caked forms are reduced in size the size-fractions have. a substantially uniform composition, drying the caked forms, and then reducing the size of said caked forms which are substantially dry to provide a mass of such particle-size-distribution that all the size-fractions thereof have a substantially uniform composition.

"10. The method of producing an alkaline curing salt composition, which composition comprises bonded aggregates of physically homogeneous'particles of curing salt selectedfrom the group consisting of alkali-metal nitrite, alkali-metal nitrate and mixtures thereof, and chemically homogeneous particles of edible-ion alkaline material in kind and quantityto elevatethe pH of meat for which said composition is used, which method comprises bonding to caked forms a granular mixture of finely ground particles of constituents of said composition 'which mixture is substantially uniform throughout in composition and which contains a small amount of added Water, by compacting said granular mixture with an effecacterized by size-fractions of substantially uniform composition.

References Cited by the Examiner UNITED STATES PATENTS Hall 99-159 X Hall et a1 99159 X Hall et a1 99-159 X Sair 99159 X Phillips 71-64 X McLellan 7l64 Bush 127-63 A. LOUIS MONACELL, Primary Examiner.

HYMAN LORD, Examiner. 

1. THE METHOD OF PRODUCING AN ALKALINE CURING SALT COMPOSITION, WHICH COMPOSITION COMPRISES BONDED AGGREGATES OF PHYSICALLY HOMOGENEOUS PARTICLES OF CURING SALT SELECTED FROM THE GROUP CONSISTING OF ALKALI-METAL NITRITE, ALKALI-METAL NITRATE AND MIXTURES THEREOF, AND CHEMICALLY HOMOGENEOUS PARTICLES OF EDIBLE-ION ALKALINE MATERIAL IN KIND AND QUANTITY TO ELEVATE THE PH OF MEAT FOR WHICH SAID COMPOSITION IS USED, WHICH METHOD COMPRISES BONDING TO CAKED FORMS A GRANULAR MIXTURE OF FINELY DIVIDED PARTICLES OF THE CONSTITUENTS OF SAID COMPOSITION WHICH MIXTURE IS SUBSTANTIALLY UNIFORM THROUGHOUT IN COMPOSITION, BY COMPACTING SAID GRANULAR MIXTURE WITH AN EFFECTIVE MECHANICAL PRESSURE SUFFICIENT TO LOCK THE PARTICLES TO EACH OTHER SO THAT WHEN THE SAID CAKED FORMS ARE REDUCED IN SIZE THE SIZE-FRACTIONS HAVE A SUBSTANTIALLY UNIFORM COMPOSITION, AND THEN REDUCING THE SIZE OF SAID CAKED FORMS WHICH ARE SUBSTANTIALLY DRY TO PROVIDE A MASS OF SUCH PARTICLE-SIZE DISTRIBUTION THAT ALL THE SIZE-FRACTIONS THEREOF HAVE A SUBSTANTIALLY UNIFORM COMPOSITION. 